That apparently was the biggest plot hole in the film. If the will were invalidated, the previous will would take effect, leaving things back where they started.
My mind was blown.
And don’t get me started on the ending of the movie! His gasp when he realizes what she did- AND got away with!!!!!! That was when movies were great and stayed with you, giving great conversation at dinner tables.
Now, garbage is all the movie industry puts out, not worth wasting my life on even the trailer or commercial.